The environmental concerns, limited supply, and increasing demand for fossil fuel drives up the cost of fossil fuel rapidly. Therefore, to meet the future energy requirements, alternative energy sources for energy conversion as well as energy storage systems are equally needed. Fuel cells are environmental friendly energy conversion devices which have the potential to meet future energy needs and power generation by converting chemical energy stored in a fuel to electrical energy. Additionally, Li-ion battery is considered to be prominent due to its high energy density as well as excellent cyclic stability. However, the main limitation of Li-ion battery is scarcity in lithium sources and safety issues. Na-ion battery is one of the promising alternatives to Li-ion battery owing to its similar storage mechanism. In addition, sodium is inexpensive compared to lithium besides to its more abundance in earthâ€™s crust. The present work emphasis on the synthesis of different types of carbon based nanocomposites and their efficient applications in polymer electrolyte membrane fuel cell (PEMFC), direct ethanol fuel cell (DEFC) and sodium ion battery.